Buggy code:
private static final Pattern COMPILE = Pattern . compile ( "^[a-zA-Z0-9_]{1,16}$" ) ; private final PlotMe_Core plugin ; private final String mySQLuname ; private final String mySQLpass ; private final String mySQLconn ; private Connection conn ; public SqlManager ( PlotMe_Core plugin , String sqlusername , String sqlpassword , String sqlconnection ) { } public Connection initialize ( ) { } public String getSchema ( ) { } public void UpdateTables ( ) { } public Connection getConnection ( ) { } public void closeConnection ( ) { } private void createTable ( ) { } public void addPlot ( Plot plot , int idX , int idZ , IWorld world ) { } public void addPlot ( Plot plot , int idX , int idZ , int topX , int bottomX , int topZ , int bottomZ ) { } public void updatePlot ( int idX , int idZ , String world , String field , Object value ) { } public void addPlotAllowed ( String player , UUID uuid , int idX , int idZ , String world ) { } public void addPlotDenied ( String player , UUID playerid , int idX , int idZ , String world ) { } public void deletePlot ( int idX , int idZ , String world ) { } public void deletePlotAllowed ( int idX , int idZ , String player , UUID playerid , String world ) { } public void deletePlotDenied ( int idX , int idZ , String player , UUID playerid , String world ) { } public Plot getPlot ( String world , String id ) { Plot plot = null ; PreparedStatement statementPlot = null ; PreparedStatement statementAllowed = null ; PreparedStatement statementDenied = null ; PreparedStatement statementMetadata = null ; ResultSet setPlots = null ; ResultSet setAllowed = null ; ResultSet setDenied = null ; ResultSet setMetadata = null ; int idX = PlotMeCoreManager . getInstance ( ) . getIdX ( id ) ; int idZ = PlotMeCoreManager . getInstance ( ) . getIdZ ( id ) ; try { Connection conn = getConnection ( ) ; statementPlot = conn . prepareStatement ( "SELECT<seq2seq4repair_space>*<seq2seq4repair_space>FROM<seq2seq4repair_space>plotmePlots<seq2seq4repair_space>WHERE<seq2seq4repair_space>LOWER(world)<seq2seq4repair_space>=<seq2seq4repair_space>?<seq2seq4repair_space>AND<seq2seq4repair_space>idX<seq2seq4repair_space>=<seq2seq4repair_space>?<seq2seq4repair_space>and<seq2seq4repair_space>idZ<seq2seq4repair_space>=<seq2seq4repair_space>?" ) ; statementPlot . setString ( 1 , world ) ; statementPlot . setInt ( 2 , idX ) ; statementPlot . setInt ( 3 , idZ ) ; setPlots = statementPlot . executeQuery ( ) ; if ( setPlots . next ( ) ) { String owner = setPlots . getString ( "owner" ) ; String biome = setPlots . getString ( "biome" ) ; Date expiredDate = null ; try { expiredDate = setPlots . getDate ( "expireddate" ) ; } catch ( SQLException ignored ) { } boolean finished = setPlots . getBoolean ( "finished" ) ; PlayerList allowed = new PlayerList ( ) ; PlayerList denied = new PlayerList ( ) ; Map < String , Map < String , String > > metadata = new HashMap < > ( ) ; double customPrice = setPlots . getDouble ( "customprice" ) ; boolean forSale = setPlots . getBoolean ( "forsale" ) ; String finishedDate ; if ( finished ) { finishedDate = setPlots . getString ( "finisheddate" ) ; } else { finishedDate = null ; } boolean protect = setPlots . getBoolean ( "protected" ) ; String currentBidder = setPlots . getString ( "currentbidder" ) ; double currentBid = setPlots . getDouble ( "currentbid" ) ; boolean auctioned = setPlots . getBoolean ( "auctionned" ) ; byte [ ] byOwner = setPlots . getBytes ( "ownerId" ) ; byte [ ] byBidder = setPlots . getBytes ( "currentbidderid" ) ; UUID ownerId = null ; if ( byOwner != null ) { ownerId = UUIDFetcher . fromBytes ( byOwner ) ; } UUID currentBidderId = null ; if ( byBidder != null ) { currentBidderId = UUIDFetcher . fromBytes ( byBidder ) ; } statementAllowed = conn . prepareStatement ( "SELECT<seq2seq4repair_space>*<seq2seq4repair_space>FROM<seq2seq4repair_space>plotmeAllowed<seq2seq4repair_space>WHERE<seq2seq4repair_space>LOWER(world)<seq2seq4repair_space>=<seq2seq4repair_space>?<seq2seq4repair_space>AND<seq2seq4repair_space>idX<seq2seq4repair_space>=<seq2seq4repair_space>?<seq2seq4repair_space>AND<seq2seq4repair_space>idZ<seq2seq4repair_space>=<seq2seq4repair_space>?" ) ; <START_BUG> statementAllowed . setString ( 1 , world . class ) ; <END_BUG> statementAllowed . setInt ( 2 , idX ) ; statementAllowed . setInt ( 3 , idZ ) ; setAllowed = statementAllowed . executeQuery ( ) ; while ( setAllowed . next ( ) ) { byte [ ] byPlayerId = setAllowed . getBytes ( "playerid" ) ; if ( byPlayerId == null ) { allowed . put ( setAllowed . getString ( "player" ) ) ; } else { allowed . put ( setAllowed . getString ( "player" ) , UUIDFetcher . fromBytes ( byPlayerId ) ) ; } } setAllowed . close ( ) ; statementDenied = conn . prepareStatement ( "SELECT<seq2seq4repair_space>*<seq2seq4repair_space>FROM<seq2seq4repair_space>plotmeDenied<seq2seq4repair_space>WHERE<seq2seq4repair_space>LOWER(world)<seq2seq4repair_space>=<seq2seq4repair_space>?<seq2seq4repair_space>AND<seq2seq4repair_space>idX<seq2seq4repair_space>=<seq2seq4repair_space>?<seq2seq4repair_space>AND<seq2seq4repair_space>idZ<seq2seq4repair_space>=<seq2seq4repair_space>?" ) ; statementDenied . setString ( 1 , world ) ; statementDenied . setInt ( 2 , idX ) ; statementDenied . setInt ( 3 , idZ ) ; setDenied = statementDenied . executeQuery ( ) ; while ( setDenied . next ( ) ) { byte [ ] byPlayerId = setDenied . getBytes ( "playerid" ) ; if ( byPlayerId == null ) { denied . put ( setDenied . getString ( "player" ) ) ; } else { denied . put ( setDenied . getString ( "player" ) , UUIDFetcher . fromBytes ( byPlayerId ) ) ; } } setDenied . close ( ) ; statementMetadata = conn . prepareStatement ( "SELECT<seq2seq4repair_space>pluginname,<seq2seq4repair_space>propertyname,<seq2seq4repair_space>propertyvalue<seq2seq4repair_space>FROM<seq2seq4repair_space>plotmeMetadata<seq2seq4repair_space>WHERE<seq2seq4repair_space>LOWER(world)<seq2seq4repair_space>=<seq2seq4repair_space>?<seq2seq4repair_space>AND<seq2seq4repair_space>idX<seq2seq4repair_space>=<seq2seq4repair_space>?<seq2seq4repair_space>AND<seq2seq4repair_space>idZ<seq2seq4repair_space>=<seq2seq4repair_space>?" ) ; statementMetadata . setString ( 1 , world ) ; statementMetadata . setInt ( 2 , idX ) ; statementMetadata . setInt ( 3 , idZ ) ; setMetadata = statementMetadata . executeQuery ( ) ; while ( setMetadata . next ( ) ) { String pluginname = setMetadata . getString ( "pluginname" ) ; String propertyname = setMetadata . getString ( "propertyname" ) ; String propertyvalue = setMetadata . getString ( "propertyvalue" ) ; if ( ! ( metadata . containsKey ( pluginname ) ) ) { metadata . put ( pluginname , new HashMap < String , String > ( ) ) ; } metadata . get ( pluginname ) . put ( propertyname , propertyvalue ) ; } setMetadata . close ( ) ; plot = new Plot ( plugin , owner , ownerId , world , biome , expiredDate , finished , allowed , ( ( idX + ";"

Fix:
statementAllowed . setString ( 1 , world . toLowerCase ( ) ) ;